Motorcycle Knuckle Adaptor- Quad Lock® Suitable for Quad Lock Handlebar Fork Stem and Mirror Mounts, the Quad Lock Motorcycle Knuckle Adaptor can be integrated between the mount and the index head to provide extra height and another level of adjustability when setting your smartphone viewing angle. What's Included Motorcycle Knuckle Adaptor Tech Specs Glass filled nylon construction Stainless steel hardware 34.8mm tall, 25mm wide